SAN DIEGO — Oat shipments coming into a General Mills, Inc. facility might contain less than 0.5% wheat, which may not seem like much until one considers a gluten-free threshold. Food and Drug Administration regulations require less than 20 parts per million of product, including oats, contain gluten to be classified as gluten-free.
“If you’re at a half per cent (of wheat), that’s a significant amount of gluten,” said Paul Wehling, principal scientist for General Mills, on Oct. 9 in San Diego at Cereals 17, the annual meeting of AACC International.
Oat loads arriving at the company’s facility might have gluten ranging from 200 p.p.m. to 1,000 p.p.m.
“And our process takes it down to less than 20 (p.p.m.),” Mr. Wehling said. “So in our process, we do get 2- to 3-log reduction of the gluten.”
General Mills, Minneapolis, uses ELISA (enzyme-linked immunosorbent assay) testing and visual inspection to find unwanted gluten-containing grains such as wheat in oats. The company does not employ lateral flow testing and relies on hand inspection instead.
“We find that doing hand inspection is much more efficient because we can look at quite a few more seeds,” Mr. Wehling said.
Systems involving blending, processing or handling should be validated for maintaining gluten-free status.
“Make sure that you can pick up a positive contaminant grain in your stream if you spiked it in,” he said.
Laura K. Allred, regulatory and standards manager for the Gluten Intolerance Group, Auburn, Wash., also spoke in the Oct. 9 presentation. A gluten-free certification organization run by the group requires gluten-free product be under 10 p.p.m. of gluten, which is stricter than the F.D.A. requirement.
Ms. Allred said gluten-containing grains wheat and barley may commingle with oats, which inherently are gluten-free. The three grains may be grown in the same locations, harvested at the same time and use the same equipment.
Companies should have fields inspected regularly. They should keep records for traceability and equipment cleaning. Equipment may need to be adjusted every year because oats are not the same size every year. Optical sorters should be checked constantly to make certain they are pulling out wheat and barley from the gluten-free oats, Ms. Allred said.Ms. Allred recommends companies use a combination of visual testing and ELISA testing.